The Mag: Penn's Mike Murphy on Efficiency Analysis

Nathaniel Badder is the Director of Men's National Teams for U.S. Lacrosse and a contributing to Inside Lacrosse. His story "A Numbers Game" appears in the October Issue of Inside Lacrosse Magazine. Here, he talks with Penn coach Mike Murphy about how the Quakers use efficiency to evaluate performance.

Mike Murphy spends a lot of time thinking about offensive efficiency, he just doesn’t spend a lot of time talking about it.

“It comes up for about five minutes a week,” says the Penn coach who logs at least two hours each week watching game tape and recording his team’s success rates on offense and defense.

To the uninitiated, offensive efficiency is the percentage of times a team scores relative to the number of possessions it has. An offense that scores 10 goals and has the ball 30 times in a game has an efficiency of 33.3%, a shade above the Division I average. A defense that yields only eight goals on 32 possessions boasts a success rate of 75%, impressive because it means holding its opponent to a lackluster 25% offensive efficiency.

Murphy’s interest was piqued about 10 years ago while watching the Penn basketball team practice and speaking with longtime coach Fran Dunphy. Recalls Murphy, “He would look at points per possession and that really stuck with me. [Lacrosse] people were looking at it for man-up and man-down, but not the rest of the time. And that didn't make sense to me.”

Goals scored and goals allowed are natural gauges for offenses and defenses, but they don’t really tell the whole story. A team that slows the ball down on offense and cherishes long possessions will likely give up fewer goals on defense than will a team that runs and guns and shoots the minute a player steps over the restraining line. It’s simple math: the longer you possess the ball, the less time your opponent can; the less time your opponent has the ball, the fewer chances they have to score.

“You can’t always look at goals per game,” says Murphy. “What you do with your possessions is what really counts.”

But, to Murphy, offensive efficiency remains more useful as a measure than as a mantra. It’s the product, not the process itself.

“It allows people to logically follow a plan and measure success,” he says. “If you look at a boxes core and see we only scored nine goals, that’s not so good. But, if you also see that we only had 24 or 25 possessions, that’s not too bad.”

Like so many coaches, though, Murphy admits to being “consumed by the process.” And, Quakers coaches still focus their eyes and whistles on how players shoot and move the ball on offense. But, he adds, “[Talking about offensive efficiency is] a way for us to teach people to value the ball.”

And, that’s one of the two most obvious ways to take advantage of this information. “You can either make the pie bigger, or make your slice bigger within the pie,” he says. That is, to generate more goals each game, you can either create more possessions or convert on the possessions you do have more frequently. And, offensive efficiency can be the conduit to this transformation.

So, why hasn’t offensive efficiency overtaken goals per game as the telltale sign of how good a team’s offense is? There are a couple of reasons.

First, as Penn’s 3-10 record from 2011 suggests, focusing on offensive efficiency doesn’t instantly and unambiguously translate into success on the field. Second, this isn’t the NBA and there is a limitation of resources. With college staffs limited to four or five coaches and support staff, there simply aren’t enough man-hours to devote adequate attention to this burgeoning science. And third, as Murphy is careful to point out, no matter how closely you study numbers like these, “It still comes down to level of effort and degree of execution on the field.”

Another Shade of Statistical Analysis

When asked what else in the sport he would like to see measured, Murphy takes a slightly different tack.

“What about graduation rates or GPAs?” he wonders. “As much as we break this stuff down, we are paid by institutions of higher learning to educate young men. It would be nice to measure or track some of the other stuff we’re doing. We are responsible for developing these young men. We need to be able to speak to that and justify the investment these colleges are making into this. The things you learn on the field are really important and impossible to teach in the classroom.”

Based on the most recent data available (2001-4), men’s lacrosse tied with skiing and gymnastics for the top NCAA graduation success rate and ranked third among men’s sports in the federal graduation success rate (the NCAA rate includes more students, including transfers and others not federally-mandated).